Understanding the evolutionary mechanisms that have shaped animal cognition is a cornerstone of animal behavior research. Cognitive processes govern many aspects of an individual’s life and thus cognitive abilities have an immense impact on fitness. In order to understand how animal cognition has evolved, it is paramount to quantify individual variation in cognitive traits across individuals, to examine non-cognitive factors that potentially influence this variation, and to examine fitness consequences of cognition.
Barn swallows breed either in solitary pairs or in colonies with multiple breeding pairs. Therefore, this species is an ideal system to make ecologically and phylogenetically controlled comparisons of cognitive traits among individuals of the same population with a varying degree of sociality.I obtained an NSF postdoctoral fellowship to evaluate the impacts of social breeding on the evolution of cognitive traits. I will be measuring individual variation in cognitive traits and their impact on reproductive success. I will also test natal and environmental influences on these traits tested along a low-high degree of sociality continuum.
Female choice for male cognitive abilities in the budgerigar (Melopsittacus undulatus)
Cognitive abilities are critical for gaining access to valuable resources. In socially monogamous birds with biparental care, choosing a male with high cognitive abilities might strongly influence the reproductive success of a female. However, the role of female mate choice in the evolution of cognitive skills is still poorly understood. My results show an intriguing role of male cognitive abilities in both male mating success and reproductive success. More on results of this study coming up soon!
Personality and cognitive performance
Animals exhibit different personality types (e.g. bold vs. shy), also commonly referred to as ‘behavioral syndromes’. These personality types are often defined based on consistency of exploratory behaviors as well as physiological responses, such as the ability to respond to stressful situations. Along with behavioral traits, these physiological responses are defined as ‘copying styles’ (e.g. proactive vs. reactive). Copying styles can potentially influence a bird’s ability to exploit novel food sources or find new sources of food, which require a suite of cognitive abilities. I explored the effects of personality on cognitive performance in captive budgerigars by measuring multiple behavioral traits as well as their response to stress. Although stress response was not a predictor of cognitive performance, we showed that personality is linked to performance in some, but not all cognitive tasks. This research was conducted in collaboration with Dr. Jodie Jawor. Read the article here.
Effects of the audience on male song structure
The warble is a very complex and plastic song only produced by male budgerigars. It is thought that this song plays a major role in reproduction by stimulating female reproductive behaviors. However, it is still unclear why male budgerigars also warble to males. As a first approach to this question, we investigated the acoustic differences between warble songs directed toward males and directed toward females. This work was conducted by Cole Tobin for his undergraduate thesis with the support of the Howard Hughes Medical Institute Program. Read the article here.
Evolution of contact calls in Neotropical parrots
Learned behaviors have been traditionally though to evolve faster than other traits (e.g. morphological traits). We evaluated the evolutionary rate of learned contact calls of Neotropical parrots and the interplay of morphology and ecology in the evolution of these signals. We did not find support for the acoustic adaption hypothesis. We did find support for correlated evolution of call duration, and call frequency with morphological measures. More importantly, we demonstrate that parrot contact calls, which are learned acoustic signals, show similar evolutionary rates to morphological traits. This research was conducted in collaboration with Marcelo Araya-Salas and Dr. Timothy Wright. Read the article here.
Creating a 3D model of a male zebra cichlid (left) and female zebra cichlid (right). I studied female mate preferences in the African Cichlid Metraclima zebra from Lake Malawi. I used computer animations of males to test female preference for dark barring patterns on the male. I hypothesized that females identify conspecific males from heterospecifics by the patterns of dark barring. Females showed no preference for the conspecific male even when a model of a heterospecific male was presented to them. This research was conducted in Bowling Green State University under the supervision of Dr. Moira van Staaden. Learn more about this study here.
Intra and inter specific aggressive displays in birds
Two Blue-grey tanagers (Thraupis episcopus) fighting over food. For my undergraduate thesis I studied the aggressive interactions among birds that visited an artificial feeder in Caracas, Venezuela. I tested the idea that different species modify the visual (i.e. postures) and acoustic components (i.e. aggressive vocalizations) according to the identity (i.e. species) of the receptor. My results suggest that aggressive displays are conserved across the avian species examined and they are not modified according to the species of the receptor. This research was conducted at the Instituto de Biología Experimental, Universidad Central de Venezuela under the supervision of Dr. Zaida Tárano and Dr. Luis Levin.
Angela Medina-García 2018 | Angela.MedinaGarcia@colorado.edu | Safran Lab Dept. of Ecology and Evolutionary Biology, CU Boulder | Boulder, CO